. >> let us continue each day to be inspired by nelson mandela's lifelong example to keep walking for a better world. >> reporter: a tribute to a man who really did change the world. danielle nottingham, cbs news, washington. >> president obama has ordered flags to fly at half staff through monday in honor of nelson mandela. >>> four months after he was released from prison, nelson mandela visited the u.s. more than 70,000 people packed the oakland coliseum to see him. as christin ayers explains, it was the east bay who led this movement that earned the bay area its visit. >> reporter: a lone rose left as the monument. >> it is you. the people of oakland, the people of the bay area who have given me and my delegation strength and hope to go back and continue the struggle. >> reporter: it was no accident that nelson mandela made oakland the final stop on his 1990 u.s. freedom tour. the east bay was really a center of a lot of the efforts to try to change the south african regime and get rid of apartide. seven years later the city of berkeley became the first in the nation to divest fro